Anaemia predicts cardiovascular events in patients with stable coronary artery disease

Abstract

Background: Anaemia is an independent risk factor for cardiovascular (CV) events in patients with heart failure and patients with chronic kidney disease. The effect of anaemia on CV outcomes in patients with coronary artery disease (CAD) remains unclear. Therefore, we investigated the prognostic value of anaemia in this group of patients.

Methods: Patients with stable angina pectoris, referred for a first diagnostic coronary angiography, were eligible for this study. Only subjects with significant coronary artery disease (>50% luminal narrowing) were used for analysis (n=143). Cardiovascular events were defined as cardiovascular death, acute myocardial infarction and hospitalisation for unstable angina pectoris. Anaemia was defined according to WHO criteria as haemoglobin level ≤8 mmol/l in men and ≤7.5 mmol/l in women.

Results: The mean age of the population was 61.5±9.4 years. During follow-up (44±19 months), 19 CV events occurred. The diagnosis of anaemia predicted CV events, even when adjusted for other risk factors (hazard ratio 5.73, 95% confidence interval 1.49-22.13, p=0.01). In univariate analysis, serum erythropoietin levels predicted CV outcomes (p<0.05); however, this association was lost when adjusted for haemoglobin concentration.

Conclusion: Anaemia is associated with worse outcome in patients with established CAD and could be used as a prognostic indicator in this group of patients.

Keywords: anaemia; coronary artery disease; prognostic factors.